This invention relates to a quality sensing device arranged at the output of a draw frame. The sliver, as it emerges from the output roll assembly of the drafting unit, passes through a sliver guide and a sliver trumpet, and the quality of the sliver may be measured.
In practice the quality of the drafted sliver is analyzed by examining the finished sliver outputted by the draw frame. The quality of the sliver, particularly the CV value of the mass uniformity, the mixture ratio and the sliver number is measured as the sliver passes through the sliver trumpet. In this arrangement a determination of, for example, the sliver mass deviations may be made only as related to the entire cross section of the sliver.